How severe is CVE-2026-27016?

CVE-2026-27016 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-27016 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27016?

CVE-2026-27016 affects Librenms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-27016?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-27016 have an EU (EUVD) identifier?

Yes. CVE-2026-27016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8036.

When was CVE-2026-27016 published?

CVE-2026-27016 was published on 2026-02-20 and last updated on 2026-06-17.

CVE-2026-27016

CVE-2026-27016 is a medium-severity vulnerability in Librenms with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-8036
Weakness: CWE-79
Affected product: Librenms
Published: 2026-02-20
Last modified: 2026-06-17

Description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 24.10.0 through 26.1.1 are vulnerable to Stored XSS via the unit parameter in Custom OID. The Custom OID functionality lacks strip_tags() sanitization while other fields (name, oid, datatype) are sanitized. The unsanitized value is stored in the database and rendered without HTML escaping. This issue is fixed in version 26.2.0.

Frequently asked questions

What is CVE-2026-27016?: LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 24.10.0 through 26.1.1 are vulnerable to Stored XSS via the unit parameter in Custom OID. The Custom OID functionality lacks strip_tags() sanitization while other fields (name, oid, datatype) are sanitized. The unsanitized value is stored in the database and rendered without HTML escaping. This issue is fixed in version 26.2.0.
How severe is CVE-2026-27016?: CVE-2026-27016 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-27016 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27016?: CVE-2026-27016 affects Librenms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27016?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-27016 have an EU (EUVD) identifier?: Yes. CVE-2026-27016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8036.
When was CVE-2026-27016 published?: CVE-2026-27016 was published on 2026-02-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:librenms:librenms:*:*:*:*:*:*:*:*

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